QGIS API Documentation  master-6227475
QgsRasterBlock Class Reference

Raster data container. More...

#include <qgsrasterblock.h>

+ Collaboration diagram for QgsRasterBlock:

List of all members.

Public Member Functions

 QgsRasterBlock ()
 QgsRasterBlock (QGis::DataType theDataType, int theWidth, int theHeight)
 Constructor which allocates data block in memory.
 QgsRasterBlock (QGis::DataType theDataType, int theWidth, int theHeight, double theNoDataValue)
 Constructor which allocates data block in memory.
virtual ~QgsRasterBlock ()
void applyNoDataValues (const QgsRasterRangeList &rangeList)
char * bits (int row, int column)
 Get pointer to data.
char * bits (size_t index)
 Get pointer to data.
char * bits ()
 Get pointer to data.
QRgb color (int row, int column) const
 Read a single color.
QRgb color (size_t index) const
 Read a single value.
bool convert (QGis::DataType destDataType)
 Convert data to different type.
QGis::DataType dataType () const
 Returns data type.
int dataTypeSize () const
QgsError error () const
 Get error.
bool hasNoData () const
 Returns true if thee block may contain no data.
bool hasNoDataValue () const
 True if the block has no data value.
QImage image () const
 Get image if type is color.
bool isEmpty () const
 Returns true if block is empty, i.e.
bool isNoData (int row, int column)
 Check if value at position is no data.
bool isNoData (size_t index)
 Check if value at position is no data.
bool isValid () const
 Returns true if the block is valid (correctly filled with data).
double noDataValue () const
 Return no data value.
bool reset (QGis::DataType theDataType, int theWidth, int theHeight)
 Reset block.
bool reset (QGis::DataType theDataType, int theWidth, int theHeight, double theNoDataValue)
 Reset block.
bool setColor (int row, int column, QRgb color)
 Set color on position.
bool setColor (size_t index, QRgb color)
 Set color on index (indexed line by line)
void setError (const QgsError &theError)
 Set error.
bool setImage (const QImage *image)
 set image.
bool setIsNoData (int row, int column)
 Set no data on pixel.
bool setIsNoData (size_t index)
 Set no data on pixel.
bool setIsNoData ()
 Set the whole block to no data.
bool setIsNoDataExcept (const QRect &theExceptRect)
 Set the whole block to no data except specified rectangle.
void setValid (bool valid)
 Mark block as valid or invalid.
bool setValue (int row, int column, double value)
 Set value on position.
bool setValue (size_t index, double value)
 Set value on index (indexed line by line)
double value (int row, int column) const
 Read a single value if type of block is numeric.
double value (size_t index) const
 Read a single value if type of block is numeric.

Static Public Member Functions

static QString printValue (double value)
 Print double value with all necessary significant digits.
static double readValue (void *data, QGis::DataType type, size_t index)
static QRect subRect (const QgsRectangle &theExtent, int theWidth, int theHeight, const QgsRectangle &theSubExtent)
 For theExtent and theWidht, theHeight find rectangle covered by subextent.
static bool typeIsColor (QGis::DataType type)
 Returns true if data type is color.
static bool typeIsNumeric (QGis::DataType type)
 Returns true if data type is numeric.
static int typeSize (int dataType)
static QGis::DataType typeWithNoDataValue (QGis::DataType dataType, double *noDataValue)
 For given data type returns wider type and sets no data value.
static QByteArray valueBytes (QGis::DataType theDataType, double theValue)
 Get byte array representing a value.
static void writeValue (void *data, QGis::DataType type, size_t index, double value)

Private Member Functions

bool createNoDataBitmap ()
 Allocate no data bitmap.
bool isNoDataValue (double value) const
 Test if value is nodata for specific band.

Static Private Member Functions

static void * convert (void *srcData, QGis::DataType srcDataType, QGis::DataType destDataType, size_t size)
 Convert block of data from one type to another.
static QGis::DataType dataType (QImage::Format theFormat)
static QImage::Format imageFormat (QGis::DataType theDataType)
static bool isNoDataValue (double value, double noDataValue)
 Test if value is nodata comparing to noDataValue.

Private Attributes

void * mData
QGis::DataType mDataType
QgsError mError
bool mHasNoDataValue
int mHeight
QImage * mImage
char * mNoDataBitmap
size_t mNoDataBitmapSize
int mNoDataBitmapWidth
double mNoDataValue
int mTypeSize
bool mValid
int mWidth

Detailed Description

Raster data container.

Definition at line 32 of file qgsrasterblock.h.


Constructor & Destructor Documentation

Definition at line 26 of file qgsrasterblock.cpp.

QgsRasterBlock::QgsRasterBlock ( QGis::DataType  theDataType,
int  theWidth,
int  theHeight 
)

Constructor which allocates data block in memory.

Parameters:
theDataTyperaster data type
theWidthwidth of data matrix
theHeightheight of data matrix

Definition at line 42 of file qgsrasterblock.cpp.

References mDataType, mHeight, mWidth, and reset().

QgsRasterBlock::QgsRasterBlock ( QGis::DataType  theDataType,
int  theWidth,
int  theHeight,
double  theNoDataValue 
)

Constructor which allocates data block in memory.

Parameters:
theDataTyperaster data type
theWidthwidth of data matrix
theHeightheight of data matrix
theNoDataValuethe value representing no data (NULL)

Definition at line 59 of file qgsrasterblock.cpp.

References mDataType, mHeight, mNoDataValue, mWidth, and reset().

Definition at line 76 of file qgsrasterblock.cpp.

References mData, mImage, mNoDataBitmap, QgsDebugMsg, and qgsFree().


Member Function Documentation

char * QgsRasterBlock::bits ( int  row,
int  column 
)

Get pointer to data.

Parameters:
rowrow index
columncolumn index
Returns:
pointer to data

Definition at line 633 of file qgsrasterblock.cpp.

References bits(), and mWidth.

Referenced by QgsPalettedRasterRenderer::block(), QgsRasterProjector::block(), and QgsRasterDataProvider::block().

char * QgsRasterBlock::bits ( size_t  index)

Get pointer to data.

Parameters:
indexdata matrix index
Returns:
pointer to data

Definition at line 613 of file qgsrasterblock.cpp.

References mData, mHeight, mImage, mTypeSize, mWidth, and QgsDebugMsg.

Get pointer to data.

Returns:
pointer to data

Definition at line 638 of file qgsrasterblock.cpp.

References mData, and mImage.

Referenced by bits(), and setColor().

QRgb QgsRasterBlock::color ( int  row,
int  column 
) const

Read a single color.

Parameters:
rowrow index
columncolumn index
Returns:
color

Definition at line 300 of file qgsrasterblock.cpp.

References mImage.

Referenced by QgsSingleBandColorDataRenderer::block(), QgsBrightnessContrastFilter::block(), QgsHueSaturationFilter::block(), color(), setColor(), and QgsRasterFileWriter::writeImageRaster().

QRgb QgsRasterBlock::color ( size_t  index) const

Read a single value.

Parameters:
indexdata matrix index
Returns:
color

Definition at line 293 of file qgsrasterblock.cpp.

References color(), and mWidth.

bool QgsRasterBlock::convert ( QGis::DataType  destDataType)

Convert data to different type.

Parameters:
destDataTypedest data type
Returns:
true on success

Definition at line 652 of file qgsrasterblock.cpp.

References image(), imageFormat(), isEmpty(), mData, mDataType, mHeight, mImage, mTypeSize, mWidth, QgsDebugMsg, qgsFree(), typeIsColor(), typeIsNumeric(), and typeSize().

Referenced by QgsSingleBandColorDataRenderer::block().

void * QgsRasterBlock::convert ( void *  srcData,
QGis::DataType  srcDataType,
QGis::DataType  destDataType,
size_t  size 
) [static, private]

Convert block of data from one type to another.

Original block memory is not release.

Parameters:
srcDatasource data
srcDataTypesource data type
destDataTypedest data type
sizeblock size (width * height)
Returns:
block of data in destDataType

Definition at line 769 of file qgsrasterblock.cpp.

References qgsMalloc(), readValue(), size, typeSize(), value(), and writeValue().

Allocate no data bitmap.

Returns:
true on success

Definition at line 832 of file qgsrasterblock.cpp.

References mHeight, mNoDataBitmap, mNoDataBitmapSize, mNoDataBitmapWidth, mWidth, QgsDebugMsg, and qgsMalloc().

Referenced by setIsNoData(), and setIsNoDataExcept().

Returns data type.

Definition at line 137 of file qgsrasterblock.h.

Referenced by QgsRasterNuller::block(), QgsRasterProjector::block(), and setImage().

QGis::DataType QgsRasterBlock::dataType ( QImage::Format  theFormat) [static, private]
int QgsRasterBlock::dataTypeSize ( ) const [inline]

Definition at line 125 of file qgsrasterblock.h.

Referenced by setIsNoData(), and setIsNoDataExcept().

QgsError QgsRasterBlock::error ( ) const [inline]

Get error.

Definition at line 286 of file qgsrasterblock.h.

bool QgsRasterBlock::hasNoData ( ) const

Returns true if thee block may contain no data.

It does not guarantee that it really contains any no data. It can be used to speed up processing. Not the difference between this method and hasNoDataValue().

Returns:
true if the block may contain no data

Definition at line 270 of file qgsrasterblock.cpp.

References mHasNoDataValue, and mNoDataBitmap.

Referenced by QgsRasterProjector::block().

bool QgsRasterBlock::hasNoDataValue ( ) const [inline]

True if the block has no data value.

Returns:
true if the block has no data value

Definition at line 144 of file qgsrasterblock.h.

Referenced by QgsRasterNuller::block(), and QgsRasterProjector::block().

QImage QgsRasterBlock::image ( ) const

Get image if type is color.

Returns:
image

Definition at line 706 of file qgsrasterblock.cpp.

References mImage.

Referenced by QgsRasterResampleFilter::block(), convert(), and QgsRasterDrawer::draw().

QImage::Format QgsRasterBlock::imageFormat ( QGis::DataType  theDataType) [static, private]

Definition at line 149 of file qgsrasterblock.cpp.

References QGis::ARGB32, and QGis::ARGB32_Premultiplied.

Referenced by convert(), and reset().

bool QgsRasterBlock::isNoData ( int  row,
int  column 
)

Check if value at position is no data.

Parameters:
rowrow index
columncolumn index
Returns:
true if value is no data

Definition at line 337 of file qgsrasterblock.cpp.

References mWidth.

Referenced by QgsRasterInterface::bandStatistics(), QgsSingleBandPseudoColorRenderer::block(), QgsPalettedRasterRenderer::block(), QgsMultiBandColorRenderer::block(), QgsSingleBandGrayRenderer::block(), QgsRasterNuller::block(), QgsRasterProjector::block(), and QgsRasterInterface::histogram().

bool QgsRasterBlock::isNoData ( size_t  index)

Check if value at position is no data.

Parameters:
indexdata matrix index
Returns:
true if value is no data

Definition at line 307 of file qgsrasterblock.cpp.

References isNoDataValue(), mData, mDataType, mHasNoDataValue, mHeight, mNoDataBitmap, mNoDataBitmapWidth, mWidth, QgsDebugMsg, readValue(), and value().

bool QgsRasterBlock::isNoDataValue ( double  value,
double  noDataValue 
) [static, private]

Test if value is nodata comparing to noDataValue.

Parameters:
valuetested value
noDataValueno data value
Returns:
true if value is nodata

Definition at line 275 of file qgsrasterblock.cpp.

References qgsDoubleNear().

Referenced by isNoData().

bool QgsRasterBlock::isNoDataValue ( double  value) const [inline, private]

Test if value is nodata for specific band.

Parameters:
valuetested value
Returns:
true if value is nodata

Definition at line 454 of file qgsrasterblock.h.

References mNoDataValue, and qgsDoubleNear().

bool QgsRasterBlock::isValid ( ) const [inline]

Returns true if the block is valid (correctly filled with data).

An empty block may still be valid (if zero size block was requested). If the block is not valid, error may be retrieved by error() method.

Definition at line 77 of file qgsrasterblock.h.

Referenced by QgsRasterChecker::runTest().

double QgsRasterBlock::noDataValue ( ) const [inline]

Return no data value.

If the block does not have a no data value the returned value is undefined.

Returns:
No data value

Definition at line 155 of file qgsrasterblock.h.

Referenced by QgsRasterNuller::block(), and QgsRasterProjector::block().

QString QgsRasterBlock::printValue ( double  value) [static]

Print double value with all necessary significant digits.

It is ensured that conversion back to double gives the same number.

Parameters:
valuethe value to be printed
Returns:
string representing the value

Definition at line 730 of file qgsrasterblock.cpp.

References QgsDebugMsg, and value().

Referenced by QgsRasterLayerSaveAsDialog::addNoDataRow(), QgsMapToolIdentify::identifyRasterLayer(), QgsRasterLayerSaveAsDialog::setOutputExtent(), and QgsRasterTransparency::writeXML().

double QgsRasterBlock::readValue ( void *  data,
QGis::DataType  type,
size_t  index 
) [inline, static]
bool QgsRasterBlock::reset ( QGis::DataType  theDataType,
int  theWidth,
int  theHeight 
)
bool QgsRasterBlock::reset ( QGis::DataType  theDataType,
int  theWidth,
int  theHeight,
double  theNoDataValue 
)

Reset block.

Parameters:
theDataTyperaster data type
theWidthwidth of data matrix
theHeightheight of data matrix
theNoDataValuethe value representing no data (NULL)
Returns:
true on success

Definition at line 96 of file qgsrasterblock.cpp.

References imageFormat(), mData, mDataType, mHasNoDataValue, mHeight, mImage, mNoDataBitmap, mNoDataValue, mTypeSize, mValid, mWidth, QgsDebugMsg, qgsFree(), qgsMalloc(), typeIsColor(), typeIsNumeric(), typeSize(), and QGis::UnknownDataType.

bool QgsRasterBlock::setColor ( int  row,
int  column,
QRgb  color 
)

Set color on position.

Parameters:
rowrow index
columncolumn index
colorthe color to be set, QRgb value
Returns:
true on success

Definition at line 363 of file qgsrasterblock.cpp.

References mWidth.

Referenced by QgsSingleBandColorDataRenderer::block(), QgsSingleBandPseudoColorRenderer::block(), QgsMultiBandColorRenderer::block(), QgsBrightnessContrastFilter::block(), QgsSingleBandGrayRenderer::block(), and QgsHueSaturationFilter::block().

bool QgsRasterBlock::setColor ( size_t  index,
QRgb  color 
)

Set color on index (indexed line by line)

Parameters:
indexdata matrix index
colorthe color to be set, QRgb value
Returns:
true on success

Definition at line 368 of file qgsrasterblock.cpp.

References bits(), color(), mImage, and QgsDebugMsg.

void QgsRasterBlock::setError ( const QgsError theError) [inline]

Set error.

Definition at line 289 of file qgsrasterblock.h.

bool QgsRasterBlock::setImage ( const QImage *  image)

set image.

Parameters:
imageimage
Returns:
true on success

Definition at line 715 of file qgsrasterblock.cpp.

References dataType(), mData, mDataType, mHeight, mImage, mNoDataValue, mTypeSize, mWidth, qgsFree(), and typeSize().

Referenced by QgsRasterResampleFilter::block().

bool QgsRasterBlock::setIsNoData ( int  row,
int  column 
)

Set no data on pixel.

Parameters:
rowrow index
columncolumn index
Returns:
true on success

Definition at line 388 of file qgsrasterblock.cpp.

References mWidth, and setIsNoData().

Referenced by QgsRasterNuller::block(), and QgsRasterDataProvider::block().

bool QgsRasterBlock::setIsNoData ( size_t  index)

Set no data on pixel.

Parameters:
indexdata matrix index
Returns:
true on success

Definition at line 393 of file qgsrasterblock.cpp.

References createNoDataBitmap(), mHasNoDataValue, mNoDataBitmap, mNoDataBitmapWidth, mNoDataValue, mWidth, and setValue().

bool QgsRasterBlock::setIsNoDataExcept ( const QRect &  theExceptRect)

Set the whole block to no data except specified rectangle.

Returns:
true on success

Definition at line 472 of file qgsrasterblock.cpp.

References createNoDataBitmap(), dataTypeSize(), mData, mDataType, mHasNoDataValue, mHeight, mImage, mNoDataBitmap, mNoDataBitmapWidth, mNoDataValue, mWidth, QgsDebugMsg, typeIsNumeric(), typeSize(), and valueBytes().

void QgsRasterBlock::setValid ( bool  valid) [inline]

Mark block as valid or invalid.

Definition at line 80 of file qgsrasterblock.h.

bool QgsRasterBlock::setValue ( int  row,
int  column,
double  value 
)

Set value on position.

Parameters:
rowrow index
columncolumn index
valuethe value to be set
Returns:
true on success

Definition at line 358 of file qgsrasterblock.cpp.

References mWidth.

Referenced by QgsRasterNuller::block(), setIsNoData(), and QgsRasterFileWriter::writeImageRaster().

bool QgsRasterBlock::setValue ( size_t  index,
double  value 
)

Set value on index (indexed line by line)

Parameters:
indexdata matrix index
valuethe value to be set
Returns:
true on success

Definition at line 342 of file qgsrasterblock.cpp.

References mData, mDataType, mHeight, mWidth, QgsDebugMsg, and writeValue().

QRect QgsRasterBlock::subRect ( const QgsRectangle theExtent,
int  theWidth,
int  theHeight,
const QgsRectangle theSubExtent 
) [static]

For theExtent and theWidht, theHeight find rectangle covered by subextent.

The output rect has x oriented from left to right and y from top to bottom (upper-left to lower-right orientation).

Parameters:
theExtentextent, usually the larger
theWidthnumbers of columns in theExtent
theHeightnumbers of rows in theExtent
theSubExtentextent, usually smaller than theExtent
Returns:
the rectangle covered by sub extent

Definition at line 847 of file qgsrasterblock.cpp.

References QgsRectangle::height(), QgsRectangle::width(), QgsRectangle::xMaximum(), QgsRectangle::xMinimum(), QgsRectangle::yMaximum(), and QgsRectangle::yMinimum().

QGis::DataType QgsRasterBlock::typeWithNoDataValue ( QGis::DataType  dataType,
double *  noDataValue 
) [static]

For given data type returns wider type and sets no data value.

Definition at line 237 of file qgsrasterblock.cpp.

References QGis::Byte, QGis::Float32, QGis::Float64, QGis::Int16, QGis::Int32, MathUtils::max(), QgsDebugMsg, QGis::UInt16, QGis::UInt32, and QGis::UnknownDataType.

Referenced by QgsRasterFileWriter::writeDataRaster().

double QgsRasterBlock::value ( int  row,
int  column 
) const
double QgsRasterBlock::value ( size_t  index) const [inline]

Read a single value if type of block is numeric.

If type is color, returned value is undefined.

Parameters:
indexdata matrix index
Returns:
value

Definition at line 444 of file qgsrasterblock.h.

References mData, mDataType, QgsDebugMsg, and readValue().

QByteArray QgsRasterBlock::valueBytes ( QGis::DataType  theDataType,
double  theValue 
) [static]

Get byte array representing a value.

Parameters:
theDataTypedata type
theValuevalue
Returns:
byte array representing the value

Definition at line 783 of file qgsrasterblock.cpp.

References QGis::Byte, QGis::Float32, QGis::Float64, QGis::Int16, QGis::Int32, QgsDebugMsg, size, typeSize(), QGis::UInt16, and QGis::UInt32.

Referenced by setIsNoData(), and setIsNoDataExcept().

void QgsRasterBlock::writeValue ( void *  data,
QGis::DataType  type,
size_t  index,
double  value 
) [inline, static]

Member Data Documentation

Definition at line 370 of file qgsrasterblock.h.

Definition at line 346 of file qgsrasterblock.h.

Referenced by hasNoData(), isNoData(), reset(), setIsNoData(), and setIsNoDataExcept().

Definition at line 367 of file qgsrasterblock.h.

Referenced by createNoDataBitmap(), and setIsNoData().

Definition at line 337 of file qgsrasterblock.h.

Referenced by bits(), convert(), reset(), and setImage().

bool QgsRasterBlock::mValid [private]

Definition at line 331 of file qgsrasterblock.h.

Referenced by reset().


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